The D-Lite's have an optical slaved built in. Simply turn them on and now when your Speedlight pops so will the D-Lite's. In you small studio that's all you'll need.

If you want to take your Speedlight off camera you can also use the Skyport Eco that's included with the 2 head D-Lite kits and either a Skyport universal receiver and connection cable to file your speedlight if you don't have line of sight, or if you do have line of sight, you can purchased a third party optical slave like from Metz or Wein, to fire your Speedlight once the D-Lite's fire.
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Sincerely,